from math import pi

def cairo_draw( ctx, width, height ):
    LINES= 32
    MAX_THETA = .80 * pi * 2
    THETA_INC = 2.0 * MAX_THETA / (LINES-1)

    ctx.set_source_rgb (0, 0, 0)
    ctx.set_line_width (2.0)

    ctx.save()

    ctx.translate (width / 2, height / 2)
    ctx.rotate (MAX_THETA)
	
    for i in range (LINES):
        ctx.move_to (-2 * width, 0)
        ctx.line_to (2 * width, 0)
        ctx.stroke()
	    
        ctx.rotate (- THETA_INC)

    ctx.restore()

    ctx.set_line_width (6)
    ctx.set_source_rgb (1, 0, 0)

    ctx.move_to (width / 4.0, 0)
    ctx.rel_line_to (0, height)
    ctx.stroke()

    ctx.move_to (3 * width / 4.0, 0)
    ctx.rel_line_to (0, height)
    ctx.stroke()